One gets to a point where killing a faction's an enemy no longer helps too much with improving your relations with a said faction. You seem to have no issues with looking for information about how to solve Freelancer’s little dilemmas, and there are several posts about how you increase your faction reputation in the least amount of time that you might want to look up. The faction reputation system in Freelancer is relatively complex, having to do with empathy and sympathy and a bunch of other stuff.

Short answer is: the Hacker’s probably like you as much as they are going to like you already unless you get some of the Hackers friends (Outcasts and Rogues, if I recall) to like you as well (or at least not want to rip out the soft pulp of your soul.